In short
Look up if you are overpaying.
Is an appraisal required for a property tax appeal?
The IAAO glossary defines an appraisal as the act or process of developing an opinion of value. That is the one-house product a lender orders. Mass appraisal, in IAAO's Standard on Mass Appraisal, is the group process that already produced the number on the notice. A formal appeal asks a separate body to look at that printed number. Some owners arrive with a paid report. Many files open without one. Local rules decide whether a report is expected. There is no universal "bring an appraisal or stay home" switch.
Does a property tax appeal need a bank appraisal?
No. A refinance packet is not the price of admission. The question is whether the printed value is the right fight, not whether a bound report is in the folder. FairAppeal reviews your property and decides whether to file. The Fair Appeal review does not start by sending the owner out for a retail appraisal.
Related reading: what mass appraisal is and the property tax glossary.